Bagging machines



May 5, 1970 H. PERRIN BAGGING MACHINES 5 Sheets-Sheet 1 Filed Aug. 8.1967 May 5, 1970 H. PERRIN 3,509,689

- BAGGING MACHINES Filed Aug. 8. 1967 5 Sheets-Sheet 2 H. PERRIN BAGGINGMACHINES May 5, 1970 5 Sheets-Sheet 5 Filed Aug. 8, 1967 May 5, 1910 H.PERRIN 3,509,689

BAGGING MACHINES Filed Aug. 8, 1967 5 Sheets-Sheet 4.

H. PERRIN BAGG'ING MACHINES May 5, 1970 5 Sheets-Sheet 5 Filed Aug. 8.1967 m w Q United States Patent Int. Cl. B6sb 43/30 US. Cl. 53-188 13Claims ABSTRACT OF THE DISCLOSURE A bagging machine in which eachindividual bag is brought into a vertical position, and then partiallyopened by means of a pair of retractable adhesive members which hold itin the region of its neck, the invention giving provision for theintroduction to the neck of a pair of spatulate members which can beretracted to open the bag fully. When the bag is open it is held firmlybetween, on its inside, the spatulate members and, on its outside, apair of stops. The adhesive members can then be retracted further so asto release their hold on the bag. The curved spatulate members areintroduced in part longitudinally to the bag and then rotated through 90so that their contours can be taken up by the bag to be filled on thesaid retraction.

The present invention relates to bagging machines equipped with amechanical device for opening the necks of the bags.

A device of this sort is known which comprises two sensing devices eachequipped with adhesive areas, which devices, being moved towards oneanother, are applied against opposite external faces of the verticallyheld bag, then withdrawn again in order to open the bag in order toaccord with the size of the filler apparatus.

In order, in this position, to prevent the neck of the bag from closinginadvertently when filling is taking place, due to loss of adhesionbetween one of the said faces and one of the said sensing devices, theknown device is provided with means for introducing and maintaining inposition inside the open neck of the bag, a rigid ring which adapts tothe shape of said neck. Nevertheless, the introduction of such a ring isextremely dificult if it is required, once in place, to open the neck ofthe bag as wide as possible. In other words, during introduction, thereis a risk of the said ring fouling and damaging the edges of the neck ofthe bag.

In addition, in the known machines, the sensing devices incorporaterollers of adhesive material situated opposite one another and,consequently, each adhesive area is limited to the generatrix of thecorresponding adhesive roller.

Experience has shown that this area of contact is inadequate.

Moreover, the known machines ususally incorporate a distributor whichslides one bag from a horizontal stack of bags arranged on a table, oneof the sensing devices gripping the bag at the table location in ordersubsequently to bring it into a vertical position.

However, experience has shown that it is extremely difficult to make thebags slide over one another and in fact they very often stick togetherso that instead of picking up one, in fact two or three are taken.Again, the bags are stacked irregularly so that the machine varies inthe efficiency of its operation all in accordance with the nature andtype of bag employed (paper, jute, plastic).

The present invention seeks to overcome these drawbacks. It enablesuniform operation of the bagging una- 3,509,689 Patented May 5, 1970 icechine to take place and also enables a combination of several machinesto be operated in a confined space.

In accordance with the invention, the bagging machine equipped with amechanical device for opening the neck of a vertically held bag, the bagbeing held open by two sensing devices provided at their mutuallyopposite extremities with adhesive areas applied to the oppositeexternal faces of the said bag and then spaced away from one another, ischaracterised in that it comprises a vertically movable carrier on whichthere is arranged at least one pair of spacers, horizontally movable inopposite directions between a closed and an opened position, thesespecers having a spatulate form the concave portions of which aremutually opposite and which, through the medium of their convex faces,come into contact in the open or spaced condition with stops which limittheir travel. Thus, with the spacers in the closed position, it ispossible to introduce them into the half-open neck of the bag byvertical displacement of the said carrier, and then to retract them fromone another. Each of the spacers thus deflects one of the mutuallyopposite faces of the bag, enlarging the neck opening, until these facesare trapped against the said stops. The bag is then held in the verticaldirection by those parts of the edge of its neck portion which aretrapped between the said spacers and the said stops.

In an advantageous embodiment, the spatulate portions of the spacerscomprise a widened area with at least one elongated projecting lateralpart, and they are rotationally mounted in relation to an axis of thesaid carrier which axis is eccentric in relation to the said widenedspatulate portion, in such a way that in the closed position the widenedarea and the projecting part are disposed outside the bag, whilst in thespaced position they are located substantially horizontally inside thebag.

This spatula arrangement, in association with the facility for rotation,on the one hand facilitates their introduction into the neck of the bagsince their elongated portions are offered up to it, and on the otherhand facilitates the holding of the neck of the bag more or less fullyopen since the widened portion is disposed horizontally inside the bag.

Preferably, the said carrier will incorporate a fork portion integralwith the end of a moving arm, and opposed rams will be mounted on theends of the branches of the fork, the said spatulate portions beingattached to the ends of the piston rods of the said rams, more or lessat rightangles thereto, whilst the said piston rods contain helicalgrooves co-operating with fixed nuts which act as stops for limiting thetravel.

Thus, in accordance with the invention the machine can comprise a turretcarrying an even number (2n) of such arms, pivoting about a horizontalaxis, this turret indexing through angular increments of 7/11 in orderto successively bring each arm to a bag distribution and openingstation, then to a loading station. In this way, a single vehicle can beloaded simultaneously and from one position in a time which is n timesshorter than that obtainable with known machines. Moreover, a machine ofthis sort can load several vehicles simultaneously.

In an advantageous embodiment of the invention, the sensing devicescomprise adhesive areas arranged in neighbouring parallel planes andopposite each one there is arranged an elastic stop that of whose facesfacing the bag is Set back behind the adhesive area situated at the sameside of the bag. Thus, when the said areas are pressed against thecorresponding stops, the bag portions trapped by them are deformed insuch a way as to be applied more extensively against the said areas.Again, the deformation of the bag facilitates the unsticking of itswalls.

Preferably, each sensing device will incorporate an adhesive stripunreeled under the control of a ratchet wheel, the latter moved by theinteraction of its pawl with stops which trip it during the travel ofthe said sensing device.

Advantageously, the movable elements of the machine in accordance withthe invention will be controlled by pneumatic rams, this because oftheir high speed of operation.

The ensuing description, which relates to the attached drawing, given byway of a non-limitative example, will indicate how the invention may beput into effect, the features contained both in the drawing and in thedescription, self-evidently constituting part of the said invention.

FIG. 1 pictorially illustrates the distributor of the bagging machine.

FIG. 2 illustrates the device for gripping the bags and arranging themin a vertical position.

FIG. 3 is a schematic section through the sensing devices.

FIG. 3a, 3b, 3c schematically illustrate in plan view, three successivepositions of the sensing devices.

FIG. 4 illustrates the adhesive sensing devices and the spacers for theneck of the bag, mounted at the tip of a transfer fork.

FIG. 4a, 4b, 4c, illustrate the spacers in three successive positions.

FIG. 5 illustrates two bagging machines as described hereinbefore,feeding the two opposite arms of a turret whose two other arms arelocated at respective filling stations.

FIG. 6 illustrates on a larger scale, the opened bag in position beneaththe filler orifice.

FIG. 7 illustrates the same bag in full line, in the positioncorresponding to that of FIG. 6, and in broken-line in the raisedposition in which filling is about to commence.

The distributor illustrated in FIG. 1 comprises the plate 1 on whichthere are stacked bags 2 (for example 400 for loading a metric tonvehicle). The height h of the top bag of the stack is maintainedconstant vis-avis the reference datum of the machine, thanks to theprovision of a contact-breaker 6, 7, 8 controlling a ram 5 the movingpart of which is integral with the said plate 1 so that the latterautomatically raises and lowers by the required amount in order tomaintain the top bag level with a table 10.

Each bag is transferred from position 2 to position 2a on the table 10,through the medium on the one hand of a sensing device 4 equipped withan adhesive area 4a and movable vertically in both directions by meansof a ram 3, and on the other hand of a gripper 12 movable horizontally,also in both directions, under the control of a ram 11.

To this end, the sensing device 4 is brought down into contact with thetop bag of the pile carried by the plate 1, then lifted away again inorder to raise the bag to the level of the gripper 12. At the end of theoutward travel of the piston rod 11a of the ram 11 which it carries, thegripper 12 closes on the bag through the agency of a known device, suchas a piston moving against a spring inside the piston rod 11a as soon asthe latter is retracted. With this retracting movement, the bag ispicked up and separated from the stack. When that edge of the bag facingthe table 10 arrives in contact with stops 14 integral with the table,the gripper 12 opens, the rod 11a continuing its retracting movement.The bag is thus deposited upon the said table in such a fashion that thesaid edge is in contact with the stops 14.

A doctor plate 13a, operated by a ram 13 whose axis is perpendicular tothat of the ram 11, pushes the bag across the table 10 until it touchesthe retractable stops 9, after which the ram 13 returns to its initialposition.

All these co-ordinated movements finally leave the single bag which hasbeen extracted from the pile, on top of the horizontal table 10 in aposition 2a which has been 4 precisely determined by the stops 9 and 14.The bags are initially stacked on the plate 1 in such a fashion that inthis position 2a, their necks are in contact with the stops 9.

The gripper device illustrated by FIG. 2, then comes into action toplace the sack in a vertical position. This latter device, comprises apair of parallel arms 20 mounted upon a shaft 21 which pivots, about itshorizontal axis XX, in bearings 21a in the machine frame (not shown, thepivoting motion being produced by a ram 24 also mounted on the saidframe; at their free ends, the arms 20 carry grippers 23 operated byrams 22. In the vertical position of the arms 20, these grippers areopen at either side of the retractable stops 9, so that the ram 13(FIG. 1) forces the bag 2a between the jaws of the grippers 23. At thedesired moment in the cycle of operations, these jaws close over the twocorners of the bag adjacent the neck, the stops 9 retract and,simultaneously, under the action of the ram 24, the arms 20 rotatethrough about the shaft 21, returning to the horizontal position 20a.The bag is now vertical (marked 2b in the figure), with it bottom parthanging down and the neck at the top.

In this position (see in particular FIG. 4), the bag, held by the twocorners at the neck, is located between two horizontal opposed rams 30and 31 carried on the frame, whose rods are provided at their free endswith adhesive sensing devices 32 and 33. At the instant at which the arm20 commence to rotate, the rods of the rams 30 and 31 advance towardsone another in order to place the adhesive rollers 32a, 33a against theopposite faces of the bag when the latter has reached the verticalposition. In order, in accordance with the invention, to increase thearea of contact between the adhesive rollers and the external faces ofthe bag, the rollers are arranged in two parallel planes, here vertical,which are staggered in relation to one another (see FIGS. 3a to 30).Moreover, opposite each of the rollers 32a and 33a, there is provided,integral with the other roller, an elastic stop 39 or 38 of whose facesnearest the bag are set back from the position of the associated roller,the stop coming into contact with the said bag. Also, when the rollerare pressed against their respective stops, the bag which they thusentrap, is deformed so that it is applied over a large area of theadhesive rollers. The area between the latter and the bag is thuincreased and, additionally, the deformation of the bag promotes thesubsequent unsticking.

FIG. 3 illustrates a vertical section through the sensing devices 32 and33. The roller 32a is rotatable, albeit the friction torque is high,about a detachable horizontal shaft 50 connected to the housing 32b, thedetachable arrangement of the shaft facilitating the replacement of aworn roller. The assembly is such that the adhesive face is presentedexternally outside the housing of the sensing device along an adequatearcuate length of the cylindrical surface, this even when the roller isvirtually completely worn.

The tape unreels from the shaft 50 onto a shaft 51 in section of 2 or 3mm. at a time, this under the control of the rotation of a ratchet Wheelrotating in rotation to the said housing 32b and driven by pawl 53. Thehousing can slide, against the action of a spring 34, on the rod 30a ofthe ram 30. In addition, the latter carries a stop 54 which cooperateswith the pawl 53 in order to index the wheel 52 one step each time theroller 32a hits a bag.

Thus, with each extension of the rod of the ram 30, an impulse is givento the wheel 52, stemming from the stop 54 integral with the rod 30a,which impulse serves to partially renew the adhesive on the roller.

A retractable sensing device 32 of this sort, which can extend over acertain distance and grip an object sufiiciently firmly to return itproperly, can reproduce this action around 15,000 times :before a roller32a is used up, the latter usually embodying 32 metres of adhesive tapeunreeled by 2 mm. with each impulse. The roller does not have to bereplaced (considering 50 kg. bags) until after 750 metric tons ofproduct have been bagged.

The sensing device 33 is similar and symmetrically disposed in relationto the sensing device 32, and their times of contact with the bag aresimultaneous. However, the sensing device 33 is attached directly to therod 31a of the ram 31. In this case, the rotation of the roller 33awhich renews the adhesive surface, is produced by cooperation of thepawl (similar to the pawl 53) of the corresponding ratchet-wheel, with aretracted end-oftravel stop. In addition, the housing 32b of theretractable sensing device 32 carries a stop 35 which collaborates witha mobile element 36a on a relay 36 attached to the bar a, the said relaycontrolling the rams 22, 24, 30 and 31.

Thus, as soon as the sensing devices 32 and 33 come into contact withthe bag (FIG. 3b), the fixed sensing device 33 collapses the retractablesensing device 32, compressing the spring 34. The stop operates therelay 36 which causes the jaws of the gripper 23 to open, causes thearms 20 to return to the original position and causes the rams 30 and 31to retract; the sensing devices 32 and 33, which now hold the bag, eachtake with them one of the sides of the bag (FIG. 3c) during theretracting movement, so that the neck is half-opened. The neck tends totake up a generally rectangular form. However, since it is an objecthere to introduce a filler orifice of fairly large diameter, it isnecessary to produce in the neck of the bag a more or less ellipticalcrosssection so that the neck is opened to a maximum extent.

The machine in accordance with the invention is to this effect providedwith mutually opposite spacers equipped with spatulate portions and 41,the concave parts of which are opposite one another (FIG. 4). Thesespatulate portions are mounted eccentrically at the ends of the rods 42aand 43a, substantially at right-angles thereto. Each of the spatulateportions comprises, in that of its regions furthest away from theparticular rod, a widened area having at least one elongated lateralprojection part 40a or 410, outside the bag. The rods 42a and 43a,belonging to the rams 42 and 43, contain a helical groove (e.g. 42b)cooperating in each case with a fixed threaded guide 44 or acting ascylinder end block and fixed nut. The rams 42 and 43, their rods 42a and43a, and the guides 44 and 45, are arranged coaxially upon the two armsof the forked carrier arrangement A which is vertically movable andhorizontally rotatable, as will be described hereinafter (arrow f anddouble-headed arrow h).

The spacers thus close and part, executing about half a turn as they doso. When the adhesive rollers 32a and 33a commence to open the bag, thespatulate portions 40 and 41 are introduced with their projectingportions 40a and 41:: into the neck of the bag (see FIG. 4) under theaction of a ram (not shown) which depresses the fork A in the directionindicated by the arrow h. After this, the rams 42 and 43 are operatedand the helical grooves in their rods, the latter retracting, cause thespacers to part, turning as they do so, so that at the end of the travelthe walls of the bag are trapped between the spatulate portions 40 and41 and the guides 44 or 45.

The bag, now held firmly in place, cannot follow the retracting movementof the adhesive blocks any further, these blocks having completed theirfunction and continuing to retract in order not to interferesubsequently with the transfer of the open bag.

The neck of the bag successively takes up the shapes illustrated in FIG.4a and 4b, and, finally, the desired elliptical shape seen in FIG. 4c,all this thanks to the fact that the convex faces of the spatulateportions bear against the internal wall of the said bag.

All the controlling of the operations of the rams, hereinbeforedescribed, can obviously be undertaken by a program equipment.

The bag thus being suitably held open between the spatulate portions andthe blocks, it is now ready for transfer to the filling station. Inaccordance with a further feature of the invention, this transfer can beeffected by means of a turret whch can simultaneously serve severalopening and filling stations. FIG. 5 illustrates a turret with fourforked arms A, B, C and D, attached in articulating fashion to thevertical spindle of the said turret and indexing round through steps inclockwise direction (arrow 3) about the vertical axis. A mechanism, notshown, is provided for producing this indexing motion and at the sametime lowers or raises the arms two at a time, i.e. A and C or B and D,through a certain angle in relation to a datum plane. It will thus beunderstood that in each indexed position, two of the arms, e.g. A and C,are in a lowered position, each opposite an opening station, whilst theother two arms, e.g. B and D, are in a raised position, opposite fillingstations.

It will also be noted that the fork D arrives at the opening station andreceives a new bag for opening, whilst the preceding one is commencingto be filled. Thus, with two feed stations, two 50 kilo bags can befilled every six seconds, meaning 60 metric tons of product per hour.

FIG. 6 illustrates an arm such as A and C carrying an open sack 20 whicharms arrived after substantially horizontal rotation through 90 at afiller station, having been raised at this station through an angle asuch that the bag embraces the loading hopper 60. This latter positionis illustrated in broken-line in FIG. 7, this figure also schematicallyillustrating a kind of circular rail 61, coaxially disposed in relationto the turret, upon which the arms can slide during their horizontalmovement. This rail can be traversed to a position opposite the fillerstation by a ram 62 which raises the arms through the requisite angle aat this point.

The invention can advantageous be complemented by a device whichmonitors and safeguards the filling operation.

When the fork has been raised in order to enter the filler orifice intothe neck of the bag, the edges of the neck may in some cases interferewith proper positioning. In this context, the invention provides a ring63 containing holes 64, through which compressed air is blown whilst thefork is being raised. As soon as the bag is in the top position, aprogram control causes a loading top to be discharged and a bag supportelement is operated (automatic bag closing device, or support flap, allin accordance with the nature of the installation).

However, the top should not be able to discharge if the bag is notcorrectly open, if it is improperly registered or if in fact there isnot a bag in place. To this end, the loading hopper 60 is provided inaccordance with the invention with two contact-breaker stopsschematically illustrated by 65, the arms 66 of which are only operated(in co-operation with the edges of the bag) to trigger the discharge ofthe top, if the bag is correctly positioned, if this is not the case thebag is released and drops onto the floor where it can be recovered andreplaced on the stack carried by the plate 1.

The support elements are released as soon as the bag is full and thelatter drops onto a conveyor belt which removes it from the machine. Thefork descends again and the spacers are raised ready to receive the bagpresented at the next opening station.

It goes without saying that the embodiments which have been describedhereinbefore are open to modification in particular by the substitutionof equivalent technical means, without departing from the scope of thepresent invention.

What I claim is:

1. A bagging machine of the type including a loading hopper and amechanical device for opening the neck of a vertica ly held bag, saiddevice comprising: first and second sensing devices provided at theirmutually opposite extremities with adhesive areas adapted to be appliedagainst opposite external faces of said bag and then spaced apart; acarrier adapted for movement towards said loading hopper; a pair ofspacers arranged for mutually opposite horizontal movement between aclosed and an open position, mounted on said carrier, each spacer havinga portion of a curved spatulate form to have a concave and a convexsurface, said concave surfaces of said pair being mutually opposite;means for rotating said spacers about a horizontal axis substantiallyperpendicular to said spacers; and a pair of stops arranged mutuallyopposite said convex surfaces, whereby during use of the device a bag isheld between said stops and said convex surfaces when in said openposition.

2. A bagging machine according to claim 1, in which each of said spacerscomprises a widened area having an elongated laterally projectingportion and is rotatably mounted about an axis substantiallyperpendicular thereto on said carrier, the axis being eccentric inrelation to said widened area.

3. A bagging machine according to claim 1 wherein said spacers areattached to the ends of rods movable by opposing hydraulic rams, each ofsaid rods being provided with a helical groove, and wherein the carrieris provided with fixed threaded guides each associated with a rod, saidguides also comprising said pair of stops.

4. A bagging machine according to claim 3, in which said carriercomprises a two-limbed fork and a movable arm having one end integraltherewith, and in which said arms are mounted on the extremities of saidfork limbs.

5. A bagging machine according to claim 1, in which said adhesive areasare laterally displaced on from the other and lie in parallel planes,each of said sensing devices being provided with a stop member situatedbeside and behind said adhesive area and in which stop member of eachdevice is located opposite said adhesive area of the other of saiddevices.

6. A bagging machine according to claim 1, in which each of said sensingdevices includes a roll of adhesive strip material, a part of whichprovides said adhesive area, a ratchet wheel, a pawl co-operatingtherewith and a stop for tripping said pawl and ratchet wheelincrementally to unreel said strip material when a bag previouslysupported by said sensing devices is held by said spacers.

7. A bagging machine according to claim 1 provided with a bagdistributing device which comprises: a vertically movable adhesive blockcapable of lifting the top bag from a stack; a substantiallyhorizontally located rod carrying a gripper at one end, said gripperserving to grip said lifted bag; a rod retracting means; a table towhich said bag can be brought by said rod under the action of saidretracting means; a first set of stops associated with said table andagainst which said bag is brought to bear under the action of saidretracting means; bag displac ment means; a second set of stops againstwhich a neck portion of said bag is brought to bear by said bagdisplacement means; a pair of horizontally pivoted gripper arms whichgrip said bag when said neck portion bears against said second set ofstops; and gripper arm rotating means for rotating said gripper armsabout said horizontal pivots to bring said bag to an upright positionbetween said sensing devices.

8. A bagging machine according to claim 7 in which said bag displacementmeans includes a doctor plate mounted for substantially horizontalmovement in a direction at right angles to said horizontally locatedrod.

9. A bagging machine according to claim 8 in which said second set ofstops are retractable.

10. A bagging machine according to claim 1 in which said loading hopperis provided with a ring located to be within the neck of a bagimmediately prior to filling the bag, said ring being provided withorifices whereby compressed air supplied to the inside of said ring mayissue through said orifices.

11. A bagging machine according to claim 7 in which each of said spacerscomprises a widened area having an elongated laterally projectingportion and is rotatably mounted about an axis on said carrier, the axisbeing eccentric in relation to said widened area.

12. A bagging machine according to claim 11 in which said spacers areattached to the ends of rods movable by opposing hydraulic rams, each ofsaid rods being provided with a helical groove and associated with afixed threaded guide, and in which said guides also comprise said pairof stops.

.13. A bagging machine according to claim 12 in which said adhesiveareas are laterally displaced one from the other and lies in parallelplanes, each of said sensing devices being provided with a stop membersituated beside and behind said adhesive area and in which said stopmember of each device is located opposite said adhesive area of theother of said devices.

References Cited UNITED STATES PATENTS 2,702,150 2/1955 Vogt 531882,926,475 3/1960 Lee 53-63 X 2,949,714 8/1960 Davis 53-63 2,973,6123/1961 McGowan 53384 TRAVIS s. MCGEHEE, Primary Examiner U.S. Cl. X.R.5363, 384

